Danged if I know...  

The trend for Americans to drive less continues. I have several theories, and so do others.

 [Note these are miles per capita]

Long-term forecasting can be an inexact, even embarassing, affair, so I’ll avoid saying too much with too much confidence.  What I’ll do instead is present the three hypotheses laid out by the Roundtable.  For our distinguished panel, recent declines in driving are indicative of one of three trends:

1. The Interrupted Growth Hypothesis: VMT cuts are temporary and increases will resume once the economy picks up (although we know more VMT is not a required, or inevitable, part economic growth);
2. The Saturation Hypothesis: car ownership and personal travel budgets have hit their limit, so no more growth is likely;
3. The Peak Car Hypothesis: VMT has hit its peak, and history will now see a VMT decline of undetermined length.

That’s right, folks.  According to the experts, in the future VMT will either go up, go down, or stay the same. [More and chart source]

Any other theories out there?  Anyone? Bueller?

My concern is when you couple that chart with this one:

[Source]
This doesn't bode well for ethanol - which already is battling the "wall".